I’ve been messing around with overclocking my 7900xt on linux to see if I can use the same settings as I do on windows. Unfortunately, it doesn’t seem nearly as stable on linux. For some reason adjusting the memory clock by about any amount causes a lot of screen flickering. Has anyone had much success overclocking their AMD gpu with the same settings as on windows? I’m running wayland, kernel 6.7.1 with a drm patch fo fix setting power level. Using LACT to do the overclock.
Windows:
mclk: 2650 clk: 3000 voltage: 1020 power limit: 15%Linux LACT settings:
mclk: 1325 clk: 3000 voltage offset: -80 power limit: 333wIt’s a powercolor hellhound 7900xt.
> cat pp_od_clk_voltage OD_SCLK: 0: 500Mhz 1: 2815Mhz OD_MCLK: 0: 97Mhz 1: 1250MHz OD_VDDGFX_OFFSET: 0mV OD_RANGE: SCLK: 500Mhz 5000Mhz MCLK: 97Mhz 1500Mhz VDDGFX_OFFSET: -450mv 0mvCould you tell us which distro + mesa? If I understand correctly, your state 1 mclk of 2500 MHz is stable on Linux, but pushing it to 2650 (as set on Windows) causes instability?
If so, could you tell us which Adrenalin version you’re using? The voltage floor for NV31 has sort of shifted since release; several users have found that their previously stable OC’s will no longer pass vulkan memory test (for example) on 23.20 and newer. Seems to be particularly noticable with AIB models as they can have substantially higher clocks than MBA ASICs.
Fedora 39 + Mesa 23.3.2. Yea, the mclk is stable at 2500mhz default and even increasing it say 50mhz seems to cause flickering, that will sometimes go away then come back. Adrenaline version is latest, 23.12.1.
How far are you able to take mclk in Fedora without any voltage offset?
Does 1020 mV pass Vulkan memory test in Windows?
Basically no increase with default voltage either. If I bump mclk +10 it starts to flicker. Set it back to 1250 and no more flickering. I will have to test that on windows when I get some time.
huh, interesting. is the flickering like an intermittent white flash?
Also - sounds good.
I just tested memtest_vulkan on linux, everything default but set Mclk to 1300, and it passed. But, there was still some flickering, not non-stop, but every once in a while I would get a flicker.
Is this with a single display? Do you think you could capture a video of this flicker?
I’ve got 3 displays. I just noticed something interesting; if I apply my settings in LACT I notice some flicker, if I then logout of my gnome session and relogin it seems fine, no flickering yet. I’ll do some more testing.